Textured multilobal filament yarn



J1me 1963 J. E. BROMLEY ETAL 3,092,890

TEXTURED MULTILOBAL FILAMENT YARN Filed Nov. 21. 1960 2 Sheets-Sheet 1 IN V EN TORS JAMES E BPOMLEV Y W/ZL/AM H H/ALS J1me 1963 J. E. BROMLEY ETAL 3,092,390

TEXTURED MULTILOBAL FILAMENT YARN Filed Nov. 21, 1960 2 Sheets-Sheet 2 FIG. 4. 37

United States Patent 3,092 890 TEXTURED MULTILOBAL FILAMENT YARN James E. Bromley and William H. Hills, Pensacola, Fla.,

assignors, by mesne assignments, to Monsanto Chemical Company, a corporation of Delaware Filed Nov. 21, 1960, Ser. No. 70,807 13 Claims. (Cl. 28-81) This invention relates to continuous multilobal filament yarn made from thermoplastic resins and exhibiting a flutfy character and an enhanced texture having aesthetic appeal.

This application is a continuation-in-part of application Serial No. 813,902, filed May 18, 1959 (now U.S. Patent 3,024,517).

Many methods and devices are known for imparting some of the desirable properties of spun yarn to continuous filament yarn by modifying the texture thereof. As a result, numerous end uses formerly dominated by spun yarn have been opened to continuous filament yarn. Continuous filament yarn which has been modified in some manner to increase its bulk, stretch, or both of these properties has become known as a textured yarn. The types of textured yarns are classifiable and characterized by the form taken by the individual filaments after same have been subjected to a texturing operation. Such forms resulting from a change in the texture of the otherwise smooth continuous closely spaced filaments include a rather permanent crimp, loop, coil, and curl shapes. Vastly different methods and apparatus are used to impart one or more of these forms or specific characteristics to continuous filament yarn.

The present invention has to do particularly with a textured continuous filament yarn whereby the change in surface dimensions or texture thereof is obtained by putting random sinusoidal crimps in such yarn.

A textured yarn characterized as a crimped type of bulked yarn and presently having notable commercial acceptance is produced by feeding continuous filament thermoplastic yarn into a stufier box and by removing same therefi'om. By compressing the yarn into the stulfer box, the individual filaments are caused to fold or bend at a sharp angle. While in the folded condition the yarn is heat-set. The yarn is removed from the box and has an irregular, zig-zag crimp that imparts to the yarn increased volume, increased elasticity, etc.

Another commercial texturing operation wherein bulking is accomplished by crimping the yarn also utilizes the stutter box technique to induce substantially permanent crimps in the yarn. This second operation involves crimping a large number of ends in warp form followed by heat-setting of the yarn in an autoclave.

However, the yarns textured by the just described methods are characterized by the sharp elbows between the arms of the crimps induced in the yarn. That is to say, that the crimps may be regarded as a shaped configuration with the crimps defining a sharply acute angle with each other. Obviously such type of crimp formation imparts a rather harsh hand to fabric made from yarn containing such crimp. Moreover, these known crimping procedures unfortunately lower the strength of the yarn to a notable degree.

Recently there has been a revival of interst in the use of yarns having a multilobal cross-sectional shape. Although multilobal yarns have been known for many years, such revival of interest has been due to efiorts to obtain greater coverage for a given weight of yarn, as well as to new methods of spinneret manufacture which have greatly reduced the cost thereof.

It is an object of this invention to provide novel and useful filaments having a multilobal cross section and Patented June 11, 1963 having been treated so as to impart thereto enhanced bulkiness, substantially permanent crimpiness of a particular crimp configuration, and other desirable properties, the yarn yielding a thicker appearing and more capacious textile article when woven, knitted, tufted, etc., for a given weight of yarn.

Another object of this invention is to provide woven and knitted fabrics and other textile articles exhibiting a pleasant hand and constructed from filaments having a multilobal cross section and having been treated so as to impart thereto enhanced bulkiness.

Other objects will appear hereinafter.

The objects of the invention are accomplished by providing multilobal filaments prepared from a synthetic polymer and textured in a particular manner such that the filaments are crimped with the crimps assuming a curve of sines. The lobes of the filaments along the lengths thereof are randomly displaced or bent from a normally substantially symmetrical arrangement to a non-symmetrical curvilinear arrangement. In one embodiment of the invention one or more lobes are longer than the other lobes, although all the lobes may be of about the same length if desired. Multilobal filaments may be considered as having a body section and a plurality of finned sections or legs integrally joined to said body section and radially disposed upon the surface of and extending longitudinally of the body, such as yarn of X- or Y-shaped cross section. The number of lobes may be two, three, four, or more, and such multilobal filaments are prepared by conventional methods, such as by employing during spinning a spinneret adapted to produce filaments having the desired number of lobes.

The present invention will be more fully understood by reference to the following detailed description and the accompanying drawings, in which:

FIGURE 1 is a schematic view in perspective with principal parts in location illustrating one arrangement of apparatus suitable for preparing the textured filaments of this invention;

FIGURE 2 is an enlarged representation of a cross section of one form of filament having the symmetrical arrangement of lobes capable of being displaced randomly to a non-symmetrical arrangement by the apparatus shown in FIGURE 1;

FIGURE 3 is an enlarged representation of a cross section of one form of filament, showing a displacement of the long lobe of a Y-shaped yarn by the apparatus disclosed herein;

FIGURE 4 is an enlarged representation of a cross section of one form of filament, showing a displacement of one of the short lobes of a Y-shaped yarn by the apparatus disclosed herein;

FIGURE 5 is an enlarged view of one multilobal filament of the present invention, illustrating the sinusoidal crimp and the random curvilinear displacement of one of the lobes;

FIGURE 6 is a sketch of the textured yarn of the present invention, showing its fiufiy, crimpy, voluminous character and further illustrates the sinusoidal crimp therein; and

FIGURE 7 is an enlarged representation of cross sections of a bundle of filaments, showing the displacement of one of the lobes of a Y-shaped yarn and illustrating the random degree of displacement from one filament to the other at a given point along the length of the bundle.

In the continuous filament yarn treating apparatus shown schematically in FIGURE 1 to which reference is made now in particular the thermoplastic cold-drawable yarn indicated by numeral 10, such as nylon and the like, and composed of a bundle of smooth substantially parallel multilobal filaments that have not been fully oriented is supplied from a yarn source. Since the yarn is not completely oriented, it is necessary to extend the yarn to be processed in order to obtain the optimum degree of molecular orientation therein. The yarn source can be, for example, yarn package 11 previously doffed from a conventional spinning machine. While the invention will be described primarily in connection with an apparatus which employs a yarn package so-dotfed, it is to be borne in mind that this is merely for the purpose of convenient illustration and in no sense of limitation since apparatus in accordance with the present invention likewise may be employed readily for processing continuous yarn which has not been doffed previously from a spinning machine.

Yarn 1G is passed over and around one end of bobbin 12 or other yarn holder, such as a pirn or cone holding a yarn source. The yarn 1b is threaded conventionally around snubbing bar 13 which functions as a simple, uncomplex tensioning device to assist in maintaining an orderly and uniform supply of yarn. It will be perceived readily that other tensioning devices such as the gate type can be used instead of the tension device shown or that the need of a tensioning device may be eliminated entirely, From the tensioning device or bar 13- the yarn it is passed through a yarn guide 14-, if needed, and then to a rotatably arranged thread advancing means 15 that is adapted to withdraw the yarn from bobbin 12 and to supply same at a controlled supply rate and that is ope"- ated at a first delivery speed. As shown, means =15 comprises a pair of suitably mounted feed rolls, at least one of which is adapted to be positively driven. The rolls have arallel axes and en a e each other in o eration to nip suliiciently the yarn passing therethrough so that slippage or free-flight of the yarn between the rolls is minimized.

From thread advancing means 15 the yarn 10 is led downwardly and around heated stretch or draw pin 1% which heats the yarn and tends to localize the attenuation of the yarn. The pin is mounted to be stationary and axially askew with respect to the axes of the feed rolls and has a smooth yarn contact surface. After being passed around pin 16 a desired number of times, the yarn it! is directed downwardly between rotatably mounted and axially parallel wheel members 17 and 18 having a plurality of uniformly circumferentiallyspaced and longitudinally extending teeth 1? that mesh in closely spaced adjustment, said members being spaced a short distance below pin 16. Air impelling means 20 may be provided to keep the members 17 and 13 at a sufficiently low temperature that the yarn is cooled so that heat-setting of the yarn is accomplished during the first pass of the yarn between members 17 and 13. Members 17 and 18 are keyed to shafts 21 and 22 respectively or are integral therewith. To drive said wheel members in unison there are provided external contacting spur gears 23, and 24 having horizontally parallel axes, that mesh and are fixedly mounted on shafts 2d and 22. As the teeth 19 mesh, the yarn is subjected to laterally applied strains increasing and'decreasing in intensity as the yarn approaches and leaves the horizontal plane in which the axes of said 'wheel members lie and where said teeth engage the notches defined by said teeth to the greatest extent. After being directed around part of the periphery of one of the members, the yarn is directed tangentially therefrom and then around part of the periphery of a roller 25 mounted on a supporting frame for free rotation and positioned adjacent member 17. A spacer bar fixedly mounted to a frame may be a suitably equivalent spacing means for roller 25. The yarn it) is wound around member 17 and roller or spacing means 25 a plurality of times as shown in FIGURE 1 so that the yarn is properly gripped to assure proper attenuation of the yarn, the peripheral speed of members 17 and 18 in operation being substantially greater than that of means 15. The axis of said roller 25 is positioned at a slightly inclined angle with respect to the axes of members 17 and 18 so as to insure proper longitudinal distribution on and advancement along the peripheries of member 17 and roller 25, thus preventing superposition of the wraps thereon. Next, the yarn after forming the outermost convolution is fed vertically downwardly through yarn pigtail guide 26 or the like, if needed, which is suitably mounted and located below said Wheel members.

The yarn is then taken up in an orderly arrangement in a conventional manner by a suitable form of package building apparatus. As shown in FIGURE 1, the yarn It; is taken up by a ring twisting assembly generally denoted by reference number 27 which comprises a bobbin 2% adapted to be rotated by driven belt 30 in a conventional manner to collect a supply of the yarn indicated by numeral 31. The assembly further comprises a conventional vertically reciprocatable spinning ring 32 carrying a ring traveller 33 adapted to revolve freely about the bobbin 2% as the yarn is twisted a desired amount and wound on the bobbin.

It may be desirable to provide a uniform taper or bevel to at least one of the toothed wheel members while maintaining the axially parallel-relationship thereof for more even operation and, among other things, to assist in preventing possible jamming or" the wheels due to breakage of the yarn 10. Hence, when yarn breakage occurs, the yarn will tend to move outboard along said wheel instead of perhaps becoming accumulated and entangled thereon. Where the wheel members 17 and 18 are tapered and the yarn progresses longitudinally along these members in the converging direction, the extent to which the yarn is deformed into a conrugated shape as it passes between the members from the normally unbent shape will diminish with the frequency of the corrugations remaining the same. Hence, it will be observed that as a result of employing tapered wheel members, the yarn is subjected to a reduced tension between each successive engagement of the yarn and the wheel members. It should be understood that the reduced tensioning may be attained by other arrangements of the apparatus.

In FIGURE 2; a Y-shaped filament having one leg longer than the other is shown. This type of cross-section has been found to be especially amendable to the texturing operation which maybe carried out using the abovedescribed apparatus. Circle A having a radius R circumscribes the Y-shapedfilament 34 illustrated in cross section. Inscribed within the cross-sectional configuration is a circle 3 having a radius R. As can be noted circle B is eccentric with respect to circle A. The straight line distance between the center of circle A and the center of circle B is indicated as AC. It is desirable that the degree of eccentricity be at least 10 percent and up to 60 percent or more. The degree of eccentricity is the number obtained by the following expression:

AC/ R X FIGURE 3 illustrates'the bending of the long leg away from its normal position assumed during the production or" the filament, the bending being the result of the tex-turiug operation using the above-described apparatus. Line 35 extends from the tip of the long leg to the center of the circumscribable circle (not shown). Line 36 extends from the tip of the long leg in its displaced position and to the center of such circumsoribab le circle. These lines intersect to form an angle a which varies from 0 to about 45. The variation of the angle a of the filaments textured by the hereindescribed apparatus is random among the filaments and is curvilinear along the length of a given filament. This results in the improved aesthetic appearance of the novel filaments of the present invention.

FIGURE 4 illustrates the bending of one of the shorter legs toward the other short leg and away from its normal position assumed during the production of the filament, the bending being the result of the texturing operation using the above-described apparatus. Line 37 extends from the tip of the leg to the center of the circumscribable 'markedly potentially crimpable.

circle (not shown). Line 38 extends from the tip of the leg in its displaced position and to the center of such circle. These lines intersect to form an angle a as above.

FIGURE shows the sinusoidal or curved appearance of an individual filament 49, as formed according to the present invention. The bending of the lobes has been found to modify the luster highlight associated with multilobal filaments in a most advantageous manner. As can be noted the point of maximum bending of lobe 41 occurs at about the apices of the crimp and the point of minimum bending of lobe 41 occurs at about midway between successive apices.

Contrary to what one might expect, not only is the crimp sinusoidal but also the apices of the filaments are randomly spaced with respect to each other. In prior art crimping where toothed gearing or serrated engaging wheels were used, the gearing is heated and shapes the filaments into a crimped configuration with adjacent filaments having apices and straight portions extending therebetween at substantially identical points along their lengths. As illustrated in FIGURE 6 the location of the apices of the crimp of one filament with respect to the other filaments in the bundle assumes no definite pattern but is haphazard. Obviously, such an indefinite wavy pattern imparts enhanced bulk to the bundle of filaments which is quite desirable.

FIGURE 7 shows how the angle a may vary among adjacent filaments at any point along the length of the filaments. For example, angle a for any of the lobes of cross section 42 is substantially zero. On the other hand, the long leg of cross section 43 is bent to a readily noticeable extent. Other degrees of bending can be seen in this figure.

The yarn after having been heated and stretched simultaneously and then cooled and crimped simultaneously is Such potential crimp can be fully developed by subjecting the drawn, deformed thermoplastic filament yarn to a final heat treatment in a hot aqueous medium such as steam or by heat or combination of both in a relaxed or substantially relaxed condition. This post heat-relax operation as just indicated develops the potential crimpability induced in the yarn by the prior operation and simultaneously sets the thus-developed crimp, thereby imparting enhanced bulkiness, crimpiness and stretchability to the yarn.

The filaments of the present invention can be made from a wide variety of thermoplastic fiber-forming resins. The yarns can be formed by known techniques from these resins, including melt extrusion, wet spinning processes, and dry spinning processes. As examples of fiber-form- 'ing synthetic polymers which are included in the thermoplastic fiber-forming resins may be mentioned polyethylene; polypropylene; polyurethanes, copolymers of vinyl acetate and vinyl chloride; the copolymers of vinylidene chloride and a minor proportion of mono-olefinic compounds copoly-merized therewith, such as, for example, vinyl chloride; homopolymers of acrylonitrile, copolymers of acrylonitrile and a minor proportion of at least one monoolefinic compound copolymerized therewith and polymer blends containing combined acrylonitrile in a major proportion; copolymers of vinyl chloride and acrylonitrile; linear polyesters of aromatic dicarboxylic acids and dihydric compounds, such as polyethylene terephthalate and the polyester derived from terephthalic acid and bis-1,4-(hydroxymethyl) cyclohexane; linear polycarbonamides such as, for example, polyhexamethylene adipamide, polyhexamethylene sebacamide, polymeric monoaminomonocarboxylic acids, such as polymeric 6- amino caproic acid; linear polycarbonates and other fiberforming thermoplastic polymers. Mixtures of such fiberforming synthetic polymers also can be used. The process of this invention is applicable particularly for the treatment of yarn generically referred to as nylon, including nylon 66, nylon 4, nylon 6, nylon 610, nylon 11, and

their fiber-forming copolymers thereof, e.g., 6/66, 6/ 610/ 66, 66/610, etc.

Twisted yarn can be processed as well as untwisted yarn. Pretwisting of the yarn is generally unnecessary and for economic consideration is preferably avoided. The denier of the thermoplastic yarn can vary considerably, as well as the denier of the individual filaments, the ordinary deniers of commercially available yarns being completely suitable. Yarns having different compositions and deniers can be combined before being processed to produce novelty effects.

The temperature at which the yarn heating means is operated depends upon many factors including the type of yarn, the yarn linear speed, and the construction thereof. The temperature of the yarn should be elevated preferably to a temperature below the temperature at which adjacent filaments will stick during the process. However, the temperature should be sufiicient so that the yarn will be deformed or distorted by the intermeshing of the teeth of the stretching wheels without undue filament breakage. The temperature to which the yarn is subjected may be in the range of 140 C. to 240 C. when nylon 66 is processed. The surface temperature of the yarn heating means will depend on the many factors, such as the denier of the yarn and the speed of the yarn.

By employing the above-described apparatus and process, one produces a potentially or latently crimpable yarn which can be changed easily into a bulked, highly crimped, stretchable continuous filament yarn. Bulk refers to the relative volume occupied by a given weight of yarn. Hence, yarn having increased bulk, such as that of the present invention, has greater covering power and warmth. Crimped refers to the fact that the filaments contain many crimps, crinkles, curls, and the like which bend in and out in a sinuous pattern along the length of the filaments and in one or more planes. stretchable refers to the fact that the yarns of this invention are elastic and have the ability to accept a slight longitudinally applied stress and thereby to become easily extended a considerable length without permanent elongation thereof. For example, the yarn can be elongated 10 to percent or more from its untensioned or relaxed length and immediately recover from this elongation in the nature of the so-called stretch-yarns. It is preferred for some end uses to develop the potential crimpability of the yarn after same has been converted into a textile article. For instance, the stretched and deformed yarn prior to the final heat treatment advantageously may be tufted into a carpet after which the heat treatment is applied. The tufts of yarn disposed on the face of the carpet will bulk to a notable extent, thereby imparting more luxurious appearance to the carpet. -In such a manner the potential crimpability in the yarn which is on the back of the carpet and in the backing material, since it is tightly held at these points, will not be developed, thereby providing an overall more economical utilization of the yarn. It will be noted also that the tufting operation is made more convenient when the crimp is subsequently developed.

The following is an example of the above-described method of treating yarns and filaments of this invention.

Example The filaments used as a yarn source were prepared by melt spinning polyhexamethylene adipami-de, the cross section of which was Y-shaped. A yarn composed of 68 of these undrawn filaments, each of which had a denier of 60 and a twist of zero turns per inch, was Wound (from a spinning machine) onto 'a bobbin for treatment. The degree of eccentricity of the circles inscribable and circumscribable in and around a cross section of the filaments was 17 percent.

Apparatus corresponding to that in FIGURE 1 was used to treat the yarn. The yarn was unwound for treatment from the bobbin by passing same through a pair of positively driven feed rolls, the rate of withdrawal a plastic resins.

being about 100 yards per minute. From the feed rolls the yarn was led onto and around a stationary stretch pin one time, the yarn movement describing a helical path therearound. The surface temperature of the pin was maintained at 210 C. by an electric resistant heater located inside the pin and controlled by a thermistor temperature sensing control device. The yarn was fed between two metal toothed wheels meshing but not having contacting teeth. The wheels were driven in unison at a predetermined speed so that a stretch of about 350 percent occurred in the yarn between the feed rolls and withdrawal from these wheels. The yarn was passed through the wheels for an additional three times; before each pass the yarn was directed around a spaced roller. Thereupon the yarn was collected on a conventional ring twister assembly.

A tufted carpet was produced from the yarn so treated. The carpet was subjected to live steam at an elevated temperature of 130 C., thereby developing the potential crimpability therein. The resulting carpet had a fluffy, bulky appearance and possessed an aesthetic appeal. The angle a as measured above in cross sections of the yarn varied randomly along the length of the filaments.

From the foregoing it is seen that the advantages of the present invention are many. Yarns having desirable bulk characteristics are provided from a Wide range of cold-drawable filaments manufactured from thermo- The inherent properties of the treated yarn are such that they impart numerous and desirable properties in woven, non-woven, and knitted fabrics. Yarns composed of the novel multilobal cross section and having sinusoidal crimps of the present invention have increased resiliency and enhanced covering power with a very pleasant and warm hand.

Many difierent embodiments of the invention may be made without departing from the spirit and scope thereof. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments shown and described herein, except as defined in the following claims.

What is claimed is:

1. A textured filament yarn prepared from a synthetic thermoplastic polymer and having a multilobal cross section along the length of the filaments thereof characterized by having crimps assuming a curve of sines, the apices of said crimps of the individual filaments being located in a haphazard relation with respect to each other thereby to impart a fluffy appearance to the yarn, and further characterized by lobes of the filaments having been randomlybent along the lengths thereof from a normally substantially symmetrical arrangement to a non-symmetrical curvilinear arrangement, the angle formed by aline drawn between the tips of the bent lobes in the normally unbent position and the center of a circumscribable circle of said cross section intersecting a line drawn between the tips of the bent lobes in the bent position and the center of said circle being in the range of -45".

2. A textured filament yarn prepared from a synthetic thermoplastic polymer and having a trilobal cross section along the length of the filaments, the lobes of which are normally substantially equi-spaced, characterized by having crimps assuming a curve of sines, the apices of said crimps of the individual filaments being located in a haphazard relation with respect to each other thereby to impart a fluify appearance to the yarn, and further characterized by lobes of the filaments having been randomly bent along the lengths thereof from a normally substantially symmetrical arrangement to an non-symmetrical curvilinear arrangement, the angle formed by a line drawn between the tips of the bent lobes in the normally unbent position and the center of a circumscribable circle of said cross section intersecting a line drawn between the tips of the bent lobes in the bent position and the center of said circle being in the range of 045.

3. The yarn of claim 2 wherein the polymer is nylon.

4. The yarn of claim 3 wherein the nylon is nylon 66.

5. The yarn of claim 3 wherein the nylon is nylon 6.

6. The yarn of claim 2 wherein the polymer is fiberforming polyester.

7. The yarn of claim 2 wherein the polymer is polypropylene.

8. The yarn of claim 2 wherein the polymer is polyethylene.

9. The yarn of claim 2 wherein one of the lobes is longer than the other two lobes.

10. A textured filament yarn prepared from a synthetic thermoplastic polymer and having a trilobal cross section along the length of the filaments, the lobes of which are normally substantially equi-spaced, characterized by having crimps assuming a curveof sines, the apices of said crimps of the individual filaments being located in a haphazard relation with respect to each other thereby to impart a fluffy appearance to the yarn, further characterized by lobes of the filaments having been randomly bent along the lengths thereof from a normally substantially symmetrical arrangement to a non-symmetrical curvilinear arrangement, the maximum bending of the bent lobes occurring at about the apices of the crimp and the minimum bending thereof occurring at about midway between successive apices, the angle formed by a line drawn between the tips of the bent lobes in the normally unbent position and the center of a circumscribable circle of the said cross section intersecting a line drawn between the tips of the bent lobes in the bent position and the center of said circle being in the range of 045, and further characterized by having one lobe longer than the others so that the degree of eccentricity thereof is at least 10 percent.

l l. A knitted textile fabric prepared from the yarn of claim 2.

12. A woven textile fabric prepared from the yarn of claim 2'. i I l 13. A floor covering material manufactured from the yarn of claim 2.

References Cited in the file of this patent UNITED STATES PATENTS 2,945,739 Lehrnicke July 19, 1960 2,968,857 Swerdlofl Jan. 24, 1961 3,024,517 Bromley et al Mar. 13, 1962 

1. A TEXTURED FILAMENT YARN PREPARED FROM A SYNTHETIC THERMOPLASTIC POLYMER AND HAVING A MULTILOBAL CROSS SECTION ALONG THE LENGTH OF THE FILAMENTS THEREOF CHARACTERIZED BY HAVING CRIMPS ASSUMING A CURVE OF SINES, THE APICES OF SAID CRIMPS OF THE INDIVIDUAL FILAMENTS BEING LOCATED IN A HAPHAZARD RELATION WITH RESPECT TO EACH OTHER THEREBY TO IMPART A FLUFFY APPEARANCE TO BE YARN, AND FURTHER CHARACTERIZED BY LOBES OF THE FILAMENTS HAVING BEEN RANDOMLY BENT ALONG THE LENGTHS THEREOF FROM A NORMALLY SUBSTANTIALLY SYMMETRICAL ARRANGEMENT TO A NON-SYMMETRICAL CURVILINEAR ARRANGEMENT, THE ANGLE FORMED BY A LINE DRAWN BETWEEN THE TIPS OF THE BENT LOBES IN THE NORMALLY UNBENT POSITION AND THE CENTER OF A CIRCUMSCRIBABLE CIRCLE OF SAID CROSS SECTION INTERSECTING A LINE DRAWN BETWEEN THE TIPS OF THE BEING LOBES IN THE BENT POSITION AND THE CENTER OF SAID CIRCLE BEING IN THE RANGE OF 0-45*. 